Pervasive devices (also referred to as “pervasive computing devices”) have become popular in recent years as people increasingly seek “anywhere, anytime” access to services such as voice and data communications. Many pervasive devices are designed to be mobile, and may equivalently be referred to as “mobile devices” or “mobile computing devices”. Examples of mobile pervasive devices range from two-way pagers to personal digital assistants, or “PDAs” (such as the Palm Pilot, Handspring Visor™, or Compaq iPAQ) to cellular phones (such as the Nokia 6110) to multi-function devices (such as the Nokia 9110 or Qualcomm “pdQ™” smartphone). (“Visor” is a trademark of Handspring, and “pdQ” is a trademark of QUALCOMM Incorporated.) All pervasive devices are not necessarily mobile, however. Examples of this latter category include smart appliances for the home or business setting, devices which are permanently mounted in automobiles, and so forth.
Pervasive devices typically share several common characteristics:
1) limited processor speed;
2) limited memory capacity;
3) small size, which limits the richness of the data input and output interfaces (for example, small screen, limited keypad, and so forth);
4) a limited amount of software pre-installed on the device; and
5) access to limited-bandwidth networks.
The inherent drawbacks of these characteristics are further exacerbated by:
1) the need to maximize the device's relatively short battery life—which in turn prevents additional processor power or memory capacity from being added to the device; and
2) the need to simplify use of the device—which in turn reduces the desirability of supporting an “open” software installation platform in which arbitrary software packages might be added.
As people rely on pervasive devices for day-to-day information access tasks, they find that the experience can be extremely limiting. While pervasive devices vary widely in functionality and in their capabilities, some general observations for an average pervasive device can be made. First, the device typically does not have sufficient memory to store all of the information that the user requires. Indeed, most of a user's files or data are normally stored on a desktop personal computer (“PC”), laptop, or corporate server. Moreover, the device's memory limitations often prevent the user from manipulating large files, such as graphics-intensive presentations (where it might be desirable, for example, to re-order the slides within a presentation). Second, the device typically does not have the software required to access all of the data that the user might wish to use. For example, most pervasive devices are unable to run common software applications such as Microsoft® Word or Microsoft® Powerpoint. (“Microsoft” is a registered trademark of Microsoft Corporation.) Some pervasive devices, such as two-way pagers from Research In Motion (“RIM”), do not usually have a Web browser installed, and therefore the user cannot render data formatted as Web documents. Third, the device often does not have the necessary drivers installed with which to support all the data manipulation operations the user might wish to perform. For example, pervasive devices typically do not have drivers to support operations such as printing and faxing. Similarly, pervasive devices typically do not have drivers for video graphics array (“VGA”) adapters that would enable the device to display content to a projector (such as a liquid crystal display, or “LCD,” projector).
Some pervasive devices would not be considered as limited in function, although they may suffer from some of the drawbacks of limited-function devices such as poor ease-of-use (having, for example, a small screen size). Examples include the Compaq iPAQ Home Internet Appliance IA-1 and the Audrey™ home appliance from 3Com Corporation. (“Audrey” is a trademark of 3Com Corporation.) The term “Wireless Information Device”, or “WID”, will be used hereinafter to refer to this type of pervasive device as well as limited-function pervasive devices. (This term recognizes the fact that both the limited-function and full-function pervasive computing devices typically communicate using wireless communication techniques and protocols, such as 802.11, Bluetooth, and so forth.)
Various attempts have been made to address the limitations of WIDs; however, existing approaches fail to provide a satisfactory solution.
One existing approach to addressing the limitations of WIDs involves the technique of “transcoding” content into a form that is better suited for the WID. Products such as the WebSphere® Transcoding Publisher from International Business Machines (“IBM”) Corporation and Spyglass Prism from Open TV, Inc. represent examples of this class of solution. (“WebSphere” is a registered trademark of IBM.) Through transcoding, the content is programmatically manipulated for a target device. For example, the transcoding process may enable the content to be rendered effectively on a small-screen device (perhaps by altering font size, removing image files, and so forth). Typically, a “transcoding engine” located on a server or network device receives the content in its original form, performs a conversion process, and delivers the renderable format to the client device. However, these transcoding solutions only address the need to view content: they do not provide a capability to manipulate the content from the WID. For example, the transcoding process does not enable the WID to e-mail, fax, print, or project the content.
Another approach to addressing the limitations of WIDs involves supplementing the capabilities of the WID through the deployment of hardware adapters or software. For example, a special-purpose attachment (known as a “Springboard™” module) may be plugged into a Handspring Visor device to enable the device to perform additional functions such as viewing and projecting Microsoft PowerPoint files. (“Springboard” is a trademark of Handspring.) The Presenter-to-Go™ module from Margi Systems, Inc. is one instance of such an attachment. (“Presenter-to-Go” is a trademark of Margi Systems, Inc.) As another example, software may be installed on a Microsoft Pocket PC device to enable the device to print Microsoft Word files to a limited set of printers. The PrintPocketCE software from FieldSoftware Products is one instance of such a software product. However, these client-centric add-on approaches increase the cost of the WID solution significantly and sometimes far exceed the cost of the WID itself. They also require additional power, effectively reducing the WID's available battery life. Each add-on solution typically supports only a single data manipulation option (or a very limited set of options), for only a limited set of file formats (or in some cases, for a single file format). Several different add-ons may therefore be needed to enable a WID to meet a particular user's requirements. An additional disadvantage of this approach is that the extra hardware is often bulky and inconvenient to carry, whereas additional software often requires a complex installation process by end-users, consumes valuable memory on the WID, and may not interoperate effectively with existing software loaded on the WID.
Therefore, what is needed is a technique for enabling WIDs to access and manipulate data that avoids the limitations of the prior art.